Plastics sabot



United States 3,005,408 PLASTICS SABOT; Stanley P. Pro'sen, Lanham, and Fredrick R. Barnet, Kensington, Md., assignors to the United States of America 5 lant (not shown) forms no part of the-present invenas l i l ei i i 'ibt s ;tl S l To '/i02 tion. The sabot which constitutes the invention is an im- 4 Claims (CL 192 9 provement on the sabot of the patent application above- (Granted under Title 35, US. Code (1952), sec. 266) mentioned and is formed with a 'basic body portion 13 of thermosetting resin and an outer thin-walled shell 14 The invention described herein may be manufactured formed of a thermoplastic resin. and used by or :for the Government of the United States The body portion is formed with longitudinal grooves of America for governmental purposes without the pay- 15 and annular grooves 16 and with an enlarged cylinment of any royalties thereon or therefor. drical section 17 which serves as a bourrelet.

This application is a continuation-in-part of applica- The grooves 16 and 17 are filled with thermoplastic tion of Stanley P. Prosen and Fredrick R. Barnet, Serial 15 resin h th thi wall h ll i applied and this pro- No. 712,283, filed January 30, 1958, now Patent N0. vides a mechanical driving connection to impart rotary 2,983,224, for a Plastics Sabot and relates to an improved movement of the thin wall shell to the body portion of structure. the sabot. Molded integral with the thin walled shell In the Plastics sabot 0f the application Serial 2,- is an annular band of a diameter slightly larger than the 283, the basic body portion of the sabot was completely 20 bourr let to engage the riding of the gun. The thineeyel'ed y a thin sheii- This shell Was formed of a walled shell of thermoplastic resin is easily engraved by thermoplastic resin and was deformable to the extent the rifling of the gun so that in the passage of the prothat it was easily engraved y fl1e gun fifiing- The basic jectile through the gun the rifiing grooves will ensabot was formed of a thermosetting resin which was grave th b nd portion of the shell and impart a rotary hard and resistant to abrasion. In the composite sabot ti t th Projectile Th b l h h of the Original application the tbin-Walled shell snbstanjectile is fired, rides on the lands of the rifiing which act tinny covered the y P and the bourrelet, that as a bearing surface and prevent balloting of the pro- P 0f the Projeelile which rides on the lands of the jectile while in the gun barrel. Because of the physical l'ifling, was P Of this thin Walled shell and due t0 the properties of the thermosetting resin the bourrelet secresiliency of the thermoplastic material making p the tion 17 will ride smoothly on the lands of the rifling thin Whiled shell, the Projectile haiieted y deviation and will hold the projectile on a straight course. Tests from a straight line course While in the gun barrel y he conducted with this type of construction demonstrate a termed balloting) and the accuracy of the projectile was greater accuracy in hitting targets, particularly at long adversely affected. range The basic sabot in the Original application was grooved This improved accuracy is attributed to the absence longitudinally 10 Provide a mechanical connection of balloting of the projectile during travel in the gun. tween the hasie y Portion and the thin Walled sheil- The use of the thermosetting resin to form the bourrelet This Provided a keying between the two sections and provides a hard bearing surface which rides smoothly sured the rotation of the Projectile The ETOOVing was on the lands of the rifling and renders the projectile also employed to assist in the breakup of the sabot upon hi hl ff i leaving the These gThOYes dilLidedihehsfihnLininh; l'he ferward eertien eh'the heey pcfiiea is space longitudinal seetiensfrom the conical portion '10 of the slug to provide an It is an object of this invention to provide a two piece annular h 1g, Thi f an ul ll .21 which sabot formed of an inner basic body of a thermosetting ill trap h h f i d to th f d ti f resin and an outer thin walled shell partially covering h projectile the body portion and formed of a thermoplastic resin. Th Pressure i d b hi trapped hti against It is another object of this invention to provide a sabot h id f h ll cause h sabot to b k up during having a basic y Portion Which is grooved both free flight. The stresses within the body of the sabot, longitudinally and anlnlinfiy to form sections joined caused by the compression of the gases from the ignited gethel' y comparatively easily ruptured Wehsexplosive and the spinning of the projectile contribute It i a further object to provide a two piece plastics to this break-up of the sabot. The grooves 116 and 17 sabot formed Of thermosetting and thEI'mOPIBStiCS l'CSlDS insures this breakq p along regular lines so that the wherein the bourrelet is part of the hard thermosetting fli ht of h Penetrating l i not di b d. resin and the deformable portion adapted to engage and ()bviously many modifications and variations of the to be engraved by the gun rifiing is formed of the thermoplastics resin.

It is a further object of the invention to provide a two piece plastics sabot which is designed to break free of the projectile upon emerging from the gun without disturbing the accuracy of flight of the projectile.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:

FIG. 1 is a front elevation of the projectile and sabot;

FIG. 2 is a similar view before the thermoplastic shell is afiixed;

FIG. 3 is a longitudinal section; and

FIG. 4 is a cross-section on lines 4--4 of FIG. 1.

Referring to the drawing wherein like numerals desig- C :Patented Oct. 24,. .1961

. 2 1 nate like parts, in the several figures, a projectile comprising a penetrating slug having a conical forward section 10 and. a cylindrical rearward section 11 is illustrated with a sabot. The. shell section containing the propel-v present invention are possible in the light of the above teachings. It is therefore to be understood, that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What is claimed and desired to be secured by Letters Patent of the United States is:

1. A two piece plastic sabot for a projectile having a slug, said sabot comprising a basic body portion of a thermosetting resin molded onto a slug, said body portion being substantially cylindrical and having one end portion of enlarged diameter to provide a bourrelet, and a thin walled external shell of a thermoplastics resin molded about but not adhering to that portion of the body not forming the bourrelet, a portion of said shell being of a thickness to increase the diameter of the body portion and shell to be greater than the diameter of the bourrelet.

2. A two piece sabot according to claim 1 where the basic body portion is formed with external grooves and the thin wall shell formed with protuberances filling said 4-. A two'piece plastic sabot according to-claim'l wherein the portion of the thin walled shell of increased diameter is an integral'annular band of a width not greater than the bourrelet.

References Cited in the file of this patent UNITED STATES PATENTS 2,820,412 B'eeuwkes et al.- Ian. 21,- 1958 

